Dutch patent application 8900803 discloses a device for treating the outer side of aircrafts, which is more particularly designed for cleaning the wings, the body and the tail portion of an aircraft. With this well-known device means for dispensing a treatment liquid--in this case a washing liquid--are formed by brushes to be supplied with the washing liquid, which brushes are mounted for movement along the longitudinal support of each gantry and for adjustment in the vertical direction.
A problem with respect to the surface treatment of aircrafts, for which no satisfactory solution was found as yet, concerns the de-icing and anti-icing treatment of large portions of the aircraft, including movable parts, such as the flaps, as well as the stabilo and the tail portion of the aircraft.
Such a de-icing treatment has to be carried out--in freezing weather--immediately preceding the take-off of the aircraft.
The usual procedure comprises the use of a truck of the tower waggon type, provided with a tank containing glycol, a pump and a spraying lance, said vehicle being driven to the aircraft so as to carry out the de-icing treatment, after which the aircraft can ride to the runway.
In practice a number of such trucks is used for service at changing locations spread over the platform area of the airport. There is a growing opposition against this procedure due to the inherent environmental contamination which goes far beyond allowable limits and is caused by the de-icing liquid that drips off the surfaces treated by the spraying lance and is often used in excess.
Moreover, the well-known trucks can only carry a limited amount of treating liquid, so that frequent and time consuming replenishing of the liquid supply is necessary.